Not all pet carriers and crates advertised as being safe for use in vehicles perform well in crash tests, a study released Friday by a pet safety nonprofit has found.

Reston, Virginia-based Center for Pet Safety collaborated with Subaru to test commercially available crates and carriers for vehicles that claimed to offer protection in vehicles and identified three top performers.

The top-rated crate was the Gunner Kennels G1 Intermediate with 8-inch tie down straps, and the top-performing carriers were PetEgo Forma Frame Jet Set Carrier with ISOFIX-Latch Connection and the Sleepypod Mobile Pet Bed with PPRS Handilock. Safety evaluations included analysis of crate connections as well as crash testing, according to a news release.

“We are proud to help lead the charge in identifying the best crates and carriers for pet lovers everywhere, while, more importantly, making pet parents aware of the safety measures they can take and the dangers that can occur if they don’t,” Subaru spokesman Michael McHale said in the news release.

In the absence of performance standards and testing protocol for pet carriers and crates, the groups came up with their own formulas for testing. They used a child safety seat clause under Federal Motor Safety Vehicle Safety Standards (FMVSS) to create a testing procedure for the carriers, while they used the European test standard ECE R-17 to evaluate the crates. The latter test is designed to evaluate the strength of seats, their anchorages and head restraints, as crates are considered cargo.

In some of the tests, crates or carriers became projectiles, crushed the artificial test animals, became disconnected from seatbelts, or became malformed as a result of the crash.

The groups said that the lack of enforced testing protocol and performance standards increases the risk for pets to become projectiles themselves in the event of a crash— increasing the chance of injury among passengers and pets alike.

The current study is an extension of a 2013 test that evaluated the safety of harness products for pets.

“After our findings in 2013, we were eager to continue working to bring accountability to the pet products industry, while highlighting the products that will help improve safety for the entire family during their travels together,” Lindsey Wolko, Founder and CEO of Center for Pet Safety, said in the news release. “In partnership with Subaru, the 2015 studies were truly eye-opening and will once again help bring pet safety awareness to millions of pet parents around the globe.”

Subaru and Center for Pet Safety recommended that, as a general rule, pet owners choose crates that are about 6 inches longer than the body of their dogs.